The ultraviolet photolysis of CH2I2 was studied in water and salt water solutions using photochemistry and picosecond time-resolved resonance Raman spectroscopy. Photolysis in both types of environments produces mainly CH2(OH)(2) and HI products. However, photolysis of CH2I2 in salt water leads to the formation of different products/intermediates (CH2ICl and Cl-2(-)) not observed in the absence of salt in aqueous solutions. The amount of CH2(OH)(2) and HI products appears to decrease after photolysis of CH2I2 in salt water compared to pure water. We briefly discuss possible implications of these results for photolysis of CH2I2 and other polyhalomethanes in sea water and other salt aqueous environments compared to nonsalt water solvated environments. (C) 2004 American Institute of Physics.